Retrograde cerebral perfusion for intracardiac air embolism in Fontan procedure.

We report the case of a 5-year-old boy who suffered from an intracardiac air influx with suspected cerebral air embolism during the Fontan procedure. We immediately transformed the cardiopulmonary bypass circuit to perform a retrograde cerebral perfusion, which resulted in successful neuroprotection. He was extubated in the operating room without any neurological defects.

Transcatheter Approaches to Palliation for Tetralogy of Fallot.

To this day, controversy still exists regarding the optimal method to treat symptomatic neonates and infants with Tetralogy of Fallot (TOF). Symptomatic (severely cyanotic or ductal dependent) infants with TOF can undergo either a staged repair approach (consisting of initial palliation followed by complete repair) or primary repair. Traditionally, initial palliative procedures have been surgical, for example placement of a Blalock-Taussig-Thomas (BTT) shunt. Recent advances in technology have facilitated the introduction of catheter-based procedures as palliative techniques, for example, patent ductus arteriosus (PDA) stenting and right ventricular outflow tract (RVOT) stenting as more durable solutions than balloon pulmonary valvuloplasty (BPV). In this article, we discuss the rationale for these procedures, technical aspects of these procedures and outcomes data compared to traditional surgical procedures. Recent data have suggested that RVOT and PDA stenting procedures offer many advantages over traditional surgical palliative procedures as palliative methods in this patient population. This comes at a cost of increased reintervention burden, which may be considered part of the overall treatment strategy in smaller neonates and can be minimized with a focus on technical aspects and overall treatment strategies. Advanced surgical techniques are required at the eventual complete repair to negotiate removal of stent material and pulmonary artery reconstruction in some instances. Further adoption of catheter based palliative procedures for infants with symptomatic TOF has the potential to tip the outcomes towards favoring a staged approach, particularly in high-risk infants.

Anomalous Aortic Origin of the Coronary Arteries - State of the Art Management and Surgical Techniques.

Anomalous aortic origin of a coronary artery (AAOCA) can be associated with myocardial ischemia and sudden cardiac arrest. We describe and compare the management and surgical techniques for patients with AAOCA. Patients presenting to the Coronary Artery Anomalies Program are evaluated and managed following a standardized approach. Our approach and data were compared to other single-center and multi-institutional data and results. Patients with AAOCA present as an incidental finding approximately 50% of the time. Advanced axial imaging is essential to define the anatomic characteristics of this lesion. Preoperative and postoperative assessment of myocardial perfusion with provocative testing is feasible and contributes to risk stratification. The surgical techniques for AAOCA repair include coronary unroofing, transection and reimplantation, and neo-ostium creation, among others. In general, surgical repair of AAOCA can mitigate the risk of ischemia with low mortality. The specific morbidities and complications of each different technique should be considered during the surgical planning. Surgical repair of AAOCA can mitigate the risk of ischemia with a low associated mortality but with clinically relevant morbidities. Long-term follow-up is necessary to accurately balance the risks of repaired and unrepaired AAOCA.

Smaller right pulmonary artery is associated with longer survival time without scimitar vein repair.

INTRODUCTION: The optimal management of scimitar syndrome remains incompletely defined. We (1) evaluated the impact of aortopulmonary collateral (APC) occlusion, (2) compared outcomes according to surgical approach for patients who underwent surgery, and (3) identified anatomic factors associated with longer survival time without scimitar vein repair. METHODS: We conducted a single center, retrospective study of 61 patients diagnosed with scimitar syndrome between 1995 and 2019. Right pulmonary artery to total pulmonary artery cross-sectional area (RPA:PA CSA) quantitatively assessed right pulmonary artery size. Anatomical features were analyzed for association with longer survival time without scimitar vein repair. RESULTS: Median follow-up time was 6 years (Q1-Q3, 2-12), with 96% 5-year survival. Twenty-three patients underwent APC occlusion, which significantly decreased symptoms of overcirculation (100%-46%; p = .001) and systolic pulmonary artery pressure (median, 34-29 mmHg; p = .004). Twenty-three patients underwent scimitar vein repair; 5-year freedom from scimitar vein stenosis was 90% among patients who underwent a reimplantation compared with 42% in patients with baffle repair (p = .1). Three patients underwent surgery before the first year of age, with lower 5-year freedom from scimitar vein stenosis (0% vs. 84%; p < .001). On multivariate analysis, a lower RPA:PA CSA was associated with longer survival time without scimitar vein repair (p = .003). CONCLUSIONS: APC occlusion improves the clinical status of young and hemodynamically unstable patients. Repair at an early age is associated with an increased risk of scimitar vein stenosis. Scimitar vein repair might be avoided in patients with a smaller right pulmonary artery.

Midterm outcomes of pulmonary artery sling repair with and without tracheoplasty.

OBJECTIVE: Review a single-centre experience with pulmonary artery sling repair and evaluate risk factors for re-intervention. METHODS: Patients with surgically repaired pulmonary artery sling at a single institution between 1996 and 2018 were retrospectively reviewed. A univariate Cox regression analysis was used to evaluate variables for association with freedom from re-intervention. RESULTS: Eighteen patients had pulmonary artery sling repair. At operation, median age and weight were 6.9 months (interquartile range 4.1-18.1) and 9.5 kg (interquartile range 6.5-14.5), respectively. A median hospital length of stay was 12 days (interquartile range 5.8-55.3). Twelve patients (67%) had complete tracheal rings, of whom six (50%) underwent tracheoplasty (five concurrently with pulmonary artery sling repair). Airway re-intervention was required in five (83%) of the six patients who underwent tracheoplasty. One patient had intraoperative diagnosis and repair of pulmonary artery sling during unrelated lesion repair and required tracheoplasty 24 days post-operatively. One patient died 55 days after pulmonary artery sling repair and tracheoplasty following multiple arrests and re-interventions. Median post-operative follow-up for surviving patients was 6.3 years (interquartile range 11 months-13 years), at which time freedom from re-intervention was 61%. When controlling for patient and tracheal size, initial tracheoplasty was associated with decreased freedom from re-intervention (hazard ratio 21.9, 95% confidence interval 1.7-284.3, p = 0.018). CONCLUSIONS: In patients with pulmonary artery sling, tracheoplasty is associated with decreased freedom from re-intervention. In select patients with pulmonary artery sling and complete tracheal rings, conservative management without tracheoplasty is feasible. Further study is necessary to delineate objective indications for tracheoplasty.

Trends in Infant Mortality After TAPVR Repair over 18 Years in Texas and Impact of Hospital Surgical Volume.

For some congenital heart lesions, higher institutional surgical volume has been associated with better survival than in lower volume centers. The relationship between institutional surgical volume and mortality in infants after total anomalous pulmonary vein return (TAPVR) repair has not been well explored. The Texas Inpatient Public Use Data File was queried for hospitalizations including TAPVR repair in infants between January 1, 1999 and December 31, 2016. We first evaluated the change in mortality over the study period. We then evaluated associations between institutional TAPVR surgical volume and mortality using univariable analysis and multivariable analysis accounting for center effects. For secondary analyses, we evaluated the association between volume and mortality among non-mutually exclusive TAPVR subsets, including isolated TAPVR, TAPVR with other congenital heart disease (CHD), TAPVR with heterotaxy, and TAPVR with single ventricle anatomy. Of 971 surgical hospitalizations that met inclusion criteria, 62% were male. Mortality after TAPVR repair decreased over the study period from 15.1% (1999-2004) to 7.6% (2012-2016) with an odds ratio per increasing year of 0.96 (95% CI 0.92-0.99, p = 0.030). By univariable analysis, earlier era, preterm birth, lower institutional surgical volume, heterotaxy, and additional CHD were associated with increased mortality. Institutional surgical volume remained significant in multivariate analysis with an odds ratio per increase in surgical volume of every 10 patients of 0.93 (95% CI 0.90-0.96, p < 0.001). When examining by subgroup, isolated TAPVR had the lowest mortality (n = 606, mortality = 6%), compared to TAPVR with other CHD (n = 359, mortality = 20%), TAPVR with heterotaxy (n = 135, mortality = 21%), and TAPVR with single ventricle (n = 128, mortality = 23%). In all groups except those with single ventricle, higher surgical volume was associated with lower mortality in multivariate analyses (isolated TAPVR p = 0.001, TAPVR with other CHD p = 0.009, TAPVR with heterotaxy p < 0.001, TAPVR with single ventricle p = 0.161). This is the first study to demonstrate an association between institutional surgical volume and mortality after TAPVR repair. Higher volume centers are associated with lower hospital mortality after TAPVR repair, including TAPVR with other CHD.

Flexible shape-memory scaffold for minimally invasive delivery of functional tissues.

Despite great progress in engineering functional tissues for organ repair, including the heart, an invasive surgical approach is still required for their implantation. Here, we designed an elastic and microfabricated scaffold using a biodegradable polymer (poly(octamethylene maleate (anhydride) citrate)) for functional tissue delivery via injection. The scaffold's shape memory was due to the microfabricated lattice design. Scaffolds and cardiac patches (1 cm × 1 cm) were delivered through an orifice as small as 1 mm, recovering their initial shape following injection without affecting cardiomyocyte viability and function. In a subcutaneous syngeneic rat model, injection of cardiac patches was equivalent to open surgery when comparing vascularization, macrophage recruitment and cell survival. The patches significantly improved cardiac function following myocardial infarction in a rat, compared with the untreated controls. Successful minimally invasive delivery of human cell-derived patches to the epicardium, aorta and liver in a large-animal (porcine) model was achieved.

Surgical Approaches to Total Anomalous Pulmonary Venous Connection.

Total anomalous pulmonary venous connection (TAPVC) constitutes a spectrum of congenital lesions whereby the pulmonary veins remain connected to systemic venous vessels or aberrantly connect to the right atrium. Definitive management requires surgical intervention and, in patients with obstruction to pulmonary venous flow, urgent operation is required. Use of temporizing catheter-based interventions allow for optimization in hemodynamically unstable neonates. Overall, survival has significantly improved over the past decades through better perioperative management and evolution of surgical approaches to minimize post-repair pulmonary vein stenosis, which persists as a major determinant of long-term outcomes.

Remote Ischemic Conditioning Prevents Lung and Liver Injury After Hemorrhagic Shock/Resuscitation: Potential Role of a Humoral Plasma Factor.

OBJECTIVE: To evaluate the efficacy of remote ischemic conditioning (RIC) on organ protection after hemorrhagic shock/resuscitation (S/R) in a murine model. BACKGROUND: Ischemia/reperfusion resulting from S/R contributes to multiple organ dysfunction in trauma patients. We hypothesized that RIC before shock (remote ischemic preconditioning), during shock (remote ischemic "PER"conditioning), or during resuscitation (remote ischemic "POST"conditioning) could confer organ protection. We also tested the effect of ischemic conditioned plasma on neutrophil migration in vivo using transgenic zebrafish models. METHODS: C57Bl/6 mice were subjected to S/R with or without hindlimb RIC. Serum levels of alanine aminotransferase and tumor necrosis factor-alpha, and liver tumor necrosis factor-alpha and interleukin 1ß mRNA were evaluated. In some experiments, lung protein leakage, cytokines, and myeloperoxidase activity were investigated. Plasma from mice subjected to RIC was microinjected into zebrafish, and neutrophil migration was assessed after tailfin transection or copper sulfate treatment. RESULTS: In mice subjected to S/R, remote ischemic preconditioning, remote ischemic "PER"conditioning, and remote ischemic "POST"conditioning each significantly reduced serum alanine aminotransferase and liver mRNA expression of tumor necrosis factor-alpha and interleukin 1ß and improved liver histology compared with control S/R mice. Lung injury and inflammation were also significantly reduced in mice treated with remote ischemic preconditioning. Zebrafish injected with plasma or dialyzed plasma (fraction >14 kDa) from ischemic conditioned mice had reduced neutrophil migration toward sites of injury compared with zebrafish injected with control plasma. CONCLUSIONS: RIC protects against S/R-induced organ injury, in part, through a humoral factor(s), which alters neutrophil function. The beneficial effects of RIC, performed during the S/R phase of care, suggest a role for its application early in the posttrauma period.

Surgical palliation strategy does not affect interstage ventricular dysfunction or atrioventricular valve regurgitation in children with hypoplastic left heart syndrome and variants.

BACKGROUND: All 3 palliation strategies, Norwood, Sano, and Hybrid, currently used for hypoplastic left heart syndrome pose a risk of myocardial injury at different times and through different mechanisms. We sought to compare these strategies to understand longitudinal differences in interstage ventricular dysfunction and their subsequent impact on transplant-free survival and atrioventricular valve regurgitation (AVVR) as well as the relationship between adverse events and ventricular function. METHODS AND RESULTS: Serial echocardiographic reports and clinical data were reviewed for 138 children with hypoplastic left heart syndrome who underwent stage I surgical palliation (Sano: 11; Norwood: 73; Hybrid: 54) between 2004 and 2011. Stage II palliation was achieved in 92 (67%) patients (Sano: 7; Norwood: 51; Hybrid: 34). Interstage transplant-free survival, ventricular dysfunction, and AVVR were equivalent among palliation strategies. Patients with preserved ventricular function had a higher rate of transplant-free survival and freedom from AVVR, regardless of palliation strategy. Patients who had cardiac arrest, cardiopulmonary resuscitation, or extracorporeal membrane oxygenation (adverse events) experienced more transient and persistent ventricular dysfunction compared to those without adverse events. Surgical palliation strategies were not identified as risk factors for ventricular dysfunction or AVVR. CONCLUSIONS: Surgical palliation strategy does not affect mortality, interstage ventricular function, or interstage AVVR in children with hypoplastic left heart syndrome. Therefore, the different timing and mechanisms of myocardial injury among palliation strategies do not affect outcomes. Ventricular dysfunction adversely affects transplant-free survival and atrioventricular valve function. Adverse events are associated with the development of ventricular dysfunction. To improve outcomes, interstage treatment should focus on the preservation of ventricular function.

Heart failure in congenital heart disease: the role of genes and hemodynamics.

Heart failure can be a consequence of insufficient palliation of structural malformations in patients with congenital heart disease (CHD) or genetic perturbations resulting in cardiomyopathies. Although CHD is traditionally considered a pediatric clinical problem, there is a rapidly increasing population of patients surviving into adulthood with CHD and a corresponding increase in the rate of hospital admissions for adult CHD patients with heart failure. Therefore, there is recognition of the clinical importance in translating conventional heart failure pharmacotherapies to patients with CHD, improving management of heart failure in the context of structural consequences of CHD, and understanding the underlying genetic abnormalities which impact myocardial performance. Heart failure in CHD typically involves complex interactions between primary structural defects, the consequences of interventions (i.e., residual lesions), and the heart's response to enhanced myocardial mechanical stress which depends on many other genetic factors (i.e., gene modifiers). In this review, we will examine how altered genes and hemodynamic loading contribute to heart failure seen in congenital heart patients. Understanding mechanisms of myocardial response and remodeling within the congenital population can provide insight into physiological principles and improve our understanding of heart failure.

Remote cardioprotection by transfer of coronary effluent from ischemic preconditioned rabbit heart preserves mitochondrial integrity and function via adenosine receptor activation.

BACKGROUND: Coronary effluent from an isolated perfused heart undergoing ischemic preconditioning can be transferred to precondition another naïve isolated heart. We investigated the effects of this effluent on mitochondrial integrity and function following a global infarct model of ischemia/reperfusion and the role of adenosine in this model of remote preconditioning. METHODS AND RESULTS: Coronary effluent from isolated perfused rabbit hearts was collected prior to (control effluent) and during three cycles of 5-min ischemia and 10-min reperfusion (IPC effluent). Adenosine concentration was significantly increased in IPC effluent (2.6 ± 1.1 µM) versus control effluent (0.21 ± 0.06 µM, P < 0.01). Infarct size (% necrotic LV mass) after 30-min global ischemia and 90-min reperfusion was significantly reduced in hearts preconditioned with IPC effluent (IPC(eff), 23 ± 7 %) and control effluent supplemented with 2.5 µM exogenous adenosine (C(eff)+ 2.5 µM ADO, 25 ± 10 %) when compared to control effluent perfused hearts (C(eff), 41 ± 8 %, P < 0.05). Compared to C(eff) mitochondria, IPC(eff) mitochondria had preserved complex I/State3 and complex IV/State 3 respiration and outer membrane integrity, and reduced cytochrome c release. In contrast, C(eff) + 2.5 µM ADO mitochondria had improved state 2 respiration and coupling to oxidative phosphorylation, reduced reactive oxygen species production and preserved outer membrane integrity. Administration of adenosine receptor blocker 8-(p-sulfophenyl)theophylline abolished the infarct limiting effect (46 ± 7 %) and the mitochondrial integrity and function preservation of IPC effluent. CONCLUSION: Remote cardioprotection by IPC effluent preserves mitochondrial integrity and function in an adenosine receptor dependent mechanism, and although infarct size reduction can be mimicked by adenosine, IPC effluent contains additional factor(s) contributing to modulation of the mitochondrial response to ischemia/reperfusion injury.

Better Late Than Never: Definitive Anatomic Repair of Dextro-Transposition of the Great Arteries.

We present a case of anatomic repair of dextro-transposition of the great arteries (d-TGA) with ventricular septal defect (VSD) in a 55-year-old man who presented with acute heart failure. This case highlights the importance of multimodal imaging and multidisciplinary involvement in developing a comprehensive surgical and medical plan for adults with congenital heart disease. We think this is the oldest reported patient undergoing anatomic surgical repair of d-TGA with VSD.

Hybrid Interventions for Pulmonary Vein Stenosis: Leveraging Intraoperative Endovascular Adjuncts in Challenging Clinical Scenarios.

Background: Pediatric pulmonary vein stenosis (PVS) is often progressive and treatment-refractory, requiring multiple interventions. Hybrid pulmonary vein interventions (HPVIs), involving intraoperative balloon angioplasty or stent placement, leverage surgical access and customization to optimize patency while facilitating future transcatheter procedures. We review our experience with HPVI and explore potential applications of this collaborative approach. Methods: Retrospective chart review of all HPVI cases between 2009 to 2023. Results: Ten patients with primary (n = 5) or post-repair (n = 5) PVS underwent HPVI at median age of 12.7 months (range 6.6 months-9.5 years). Concurrent surgical PVS repair was performed in 7/10 cases. Hybrid pulmonary vein intervention was performed on 17 veins, 13 (76%) with prior surgical or transcatheter intervention(s). One patient underwent intraoperative balloon angioplasty of an existing stent. In total, 18 stents (9 bare metal [5-10 mm diameter], 9 drug eluting [3.5-5 mm diameter]) were placed in 16 veins. At first angiography (median 48 days [range 7 days-2.8 years] postoperatively), 8 of 16 (50%) HPVI-stented veins developed in-stent stenosis. Two patients died from progressive PVS early in the study, one prior to planned reintervention. Median time to first pulmonary vein reintervention was 86 days (10 days-2.8 years; 8/10 patients, 13/17 veins). At median survivor follow-up of 2.2 years (2.3 months-13.1 years), 1 of 11 surviving HPVI veins were completely occluded. Conclusions: Hybrid pulmonary vein intervention represents a viable adjunct to existing PVS therapies, with promising flexibility to address limitations of surgical and transcatheter modalities. Reintervention is anticipated, necessitating evaluation of long-term benefits and durability as utilization increases.

The American Association for Thoracic Surgery (AATS) 2024 expert consensus document: Management of neonates and infants with Ebstein anomaly.

OBJECTIVES: Symptomatic neonates and infants with Ebstein anomaly (EA) require complex management. A group of experts was commissioned by the American Association for Thoracic Surgery to provide a framework on this topic focusing on risk stratification and management. METHODS: The EA Clinical Congenital Practice Standards Committee is a multinational and multidisciplinary group of surgeons and cardiologists with expertise in EA. A citation search in PubMed, Embase, Scopus, and Web of Science was performed using key words related to EA. The search was restricted to the English language and the year 2000 or later and yielded 455 results, of which 71 were related to neonates and infants. Expert consensus statements with class of recommendation and level of evidence were developed using a modified Delphi method, requiring 80% of members votes with at least 75% agreement on each statement. RESULTS: When evaluating fetuses with EA, those with severe cardiomegaly, retrograde or bidirectional shunt at the ductal level, pulmonary valve atresia, circular shunt, left ventricular dysfunction, or fetal hydrops should be considered high risk for intrauterine demise and postnatal morbidity and mortality. Neonates with EA and severe cardiomegaly, prematurity (<32 weeks), intrauterine growth restriction, pulmonary valve atresia, circular shunt, left ventricular dysfunction, or cardiogenic shock should be considered high risk for morbidity and mortality. Hemodynamically unstable neonates with a circular shunt should have emergent interruption of the circular shunt. Neonates in refractory cardiogenic shock may be palliated with the Starnes procedure. Children may be assessed for later biventricular repair after the Starnes procedure. Neonates without high-risk features of EA may be monitored for spontaneous closure of the patent ductus arteriosus (PDA). Hemodynamically stable neonates with significant pulmonary regurgitation at risk for circular shunt with normal right ventricular systolic pressure should have an attempt at medical closure of the PDA. A medical trial of PDA closure in neonates with functional pulmonary atresia and normal right ventricular systolic pressure (>20-25 mm Hg) should be performed. Neonates who are hemodynamically stable without pulmonary regurgitation but inadequate antegrade pulmonary blood flow may be considered for a PDA stent or systemic to pulmonary artery shunt. CONCLUSIONS: Risk stratification is essential in neonates and infants with EA. Palliative comfort care may be reasonable in neonates with associated risk factors that may include prematurity, genetic syndromes, other major medical comorbidities, ventricular dysfunction, or sepsis. Neonates who are unstable with a circular shunt should have emergent interruption of the circular shunt. Neonates who are unstable are most commonly palliated with the Starnes procedure. Neonates who are stable should undergo ductal closure. Neonates who are stable with inadequate pulmonary flow may have ductal stenting or a systemic-to-pulmonary artery shunt. Subsequent procedures after Starnes palliation include either single-ventricle palliation or biventricular repair strategies.

Managing Bilateral Discontinuous Pulmonary Arteries of Ductal Origin in Single-Ventricle Anatomy.

BACKGROUND: We describe outcomes and management strategies for single-ventricle and bilaterally discontinuous pulmonary arteries (PAs) originating from bilateral ductus arteriosus. METHODS: We reviewed 22 patients with aforementioned anatomy and PA centralization from 1995 to 2023, excluding those with biventricular repair. RESULTS: Median age at centralization was 9 days (minimum-maximum, 0 days-2 years). Centralization was performed with systemic-to-pulmonary shunt (n =20 [91%]; 2 after bilateral ductal stents) or bidirectional cavopulmonary connection (n = 2 [9%]) using pericardial roll (n = 14 [64%]), patch-augmented direct anastomosis (n = 7 [32%]), and interposition graft (n = 1 [5%]) techniques. Concurrent total anomalous pulmonary venous connection (TAPVC, n = 11 [50%]) was associated with significantly inferior survival (P = .01). Five patients (23%) died at a median of 59 days (minimum-maximum, 6-257 days) after centralization, all with noncardiac TAPVC. At the latest follow-up for 17 survivors (median, 13.5 years; minimum-maximum, 0.5-25.1 years after centralization), 12 completed Fontan, 4 completed second-stage palliation, and 1 received a transplant before second-stage palliation. PA reintervention was required in 14 patients (64%), including 3 with reoperations independent of staged palliation. Echocardiography from baseline to before the second stage demonstrated branch PA growth with significantly increased diameters (left, P = .0006; right, P = .0002); z-scores significantly increased for right (P = .004) but not left (P = .11). CONCLUSIONS: Successful single-ventricle palliation is possible, although high risk, for patients with bilateral discontinuous ductal PAs. Early postcentralization mortality remains substantial, particularly with associated noncardiac TAPVC. Many require reintervention to maintain PA growth, typically concurrently with staged palliation.

Hybrid versus Norwood strategies for single-ventricle palliation.

BACKGROUND: Hybrid and Norwood strategies differ substantially in terms of stage II palliative procedures. We sought to compare these strategies with an emphasis on survival and reintervention after stage II and subsequent Fontan completion. METHODS AND RESULTS: Of 110 neonates with functionally single-ventricle physiology who underwent stage I palliation between 2004 and 2010, 75 (69%) infants (Norwood, n=43; hybrid, n=32) who subsequently underwent stage II palliation were studied. Survival and reintervention rates after stage II palliation, anatomic and physiologic variables at pre-Fontan assessment, and Fontan outcomes were compared between the groups. Predictors for reintervention were analyzed. Freedom from death/transplant after stage II palliation was equivalent between the groups (Norwood, 80.4% versus hybrid, 85.6% at 3 years, P=0.66). Hybrid patients had a higher pulmonary artery (PA) reintervention rate (P=0.003) and lower Nakata index at pre-Fontan evaluation (P=0.015). Aortic arch and atrioventricular valve reinterventions were not different between the groups. Ventricular end-diastolic pressure, mean PA pressure, and ventricular function were equivalent at pre-Fontan assessment. There were no deaths after Fontan completion in either group (Norwood, n=25, hybrid, n=14). CONCLUSIONS: Survival after stage II palliation and subsequent Fontan completion is equivalent between the groups. The hybrid group had a higher PA reintervention rate and smaller PA size. Both strategies achieved adequate physiology for Fontan completion. Evolution of the hybrid strategy requires refinement to provide optimal PA growth.